William e



UNITED STAT-ns PATENT OFFICE.

WILLIAM I3. MILLIGAN, or Nnw YORK, N. Y.

lNIPROVED .HRANGEMENT 0F THE FLUES AND 'WATER-SPACES OF STEAM-BOILERS.

Specication forming part of Letters Patent No. 8,226, dated July 15, 1851.

To @ZZ whom it may concern:

Be it known that I, WILLIAM E. MILLIGAN, of the city, county, and State of New York, have invented a new and Improved Steam- Boiler; and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had to the annexed drawing, making a part of this specification, which is a view in perspective of the interior of my boiler.

The nature of my invention consists in a new arrangement of fines, tubes, and waterspaces within a boiler for generating steam,

' whereby I am enabled to present a much enlarged amount of surface to the action of heat.

The construction is as follows: The general external appearance of my boiler is as of usual make, as is also the construction and arrangement of the furnace within it; but upon the upper side of the ure-place c, I place a series f of fines, b, of a number and capacity sufficient :to carry off readily the products of combus- 'ltion from the furnace. These lues open into :a horizontal fiue, c, which is placed above the jfurnace and below the water-line of the boiler. Back of the furnace a and near to the bottom (of the boiler is another horizontal flue, d, and between these horizontal iiues is a series of vertical fines similar to the fines b, but necessarily longer, as shown at e, and these flues are for the purpose of conveying the products of combustion from the upper to the lower horizontal flue. Through the center of each of the vertical ues e,I place a tube, f, of, say, one-half the diameter of the flue, and these tubes extend from the upper tube-sheet of the horizontal flue c through the lower tube-sheet of the flue (l, as shown. The water passes through these tubes, and the purpose of them is to present greater surface for the absorption of heat, as well as to insure the circulation of the water Within the boiler. From the lower horizontal flue, (l, the productof com"` bustion is either conveyed directly into the chimney or it may be returned to another upper flue, c through the fines c; thence again to another lower flue, el', through the lines c, 1 and thence into the chimney by means of the VKfines b', as shown. One, two, or more furnaces arranged with flues and tubes thus constructed may be placed within the same shell, suicient space being left between them, as shown, for the circulation of the water.

The practical operation is thus: The water iu the boiler rising above the upper horizontal flue fills the tubes fand surrounds all the flues. The product of combustion passes from the flue c, through the vertical fines e, parting with its heat on the one side to the water sur rounding those, and on the other to the water within the tubes f. The water contained in the tubes is much more rapidly heated than that surrounding the flues, as its volume lis less, and hence by known laws a regular and perfect circulation takes place within the boiler.

I do not mean or intend to limit myself to the precise form of construction herein set forth, as it is lobvious that if desirable the fines c and d may be placed vertically and the others may be horizontal.

\Vl1at I claim as of my own invention, and which I desire to secure by Letters Patent of the United States, is

The general arrangement of the tubes and dues of the boiler in the manner described that is to say, the water-tubes connected with an upper and lower tube-sheetin combination with the liu es of less length than the tubes, which ues are also connected with an upper and lower flue-sheet, whereby two horizontal liues are formed in such connection with each other by means of the vertical flues, that the product of combustion from the fire-place shall pass into the upper horizontal iiue and thence down the vertical i'lues into the lower horizontal flue, having thus the facility of parting with its heat on the one hand by radiation through the fines to the water-spaces surrounding them, andon the other through the tubes to the water circulating through those, and this whether the said tubes and iues are placed vertically or horizontally, the whole being constructed and operating substantially as herein set forth.

WV. E. MILLIGAN. Vitnesses:

S. I-I. MAYNARD.

JOHN W. KILsBY, Jr. 

